Internal-combustion engine.



S. C. KIRK.

INTERNAL COMBUSTION ENGINE. APPLICATION man ram/.21. 1910.

1,266,954. Patented May 21,1918.

3 SHEETS-SHEET I.

S. C. KIRK INTERNAL QOMBUSHON ENGINE. APPucAnau min uov.21. 1916.

Patenmd May 21,1918.

3 suns-sun 2'.

S C. KIRK. INTERNAL COMBUSTION ENGINE. APPUCAHON mm uuv. 21. [916.

3 SHEETS-SHEET 3.

Patented May 21,1918.

-citizen of the United States,

UNITED STATES PATENT OFFICE.

SHIRLEY C, KIRK, OI WIKDBOR, ILLINOIS.

INTERNAL- COM BUSTION ENGINE.

To all whom it may concern: Be it known that I, SHIRLEY C. KIRK, aresiding at Windsor, in the county of Shelby of Illinois, have inventedcertain new and useful Improvements in Internal-Combustion En 'nes, ofwhich the following is a specificafion.

My invention relates to new and useful improvements in internalcombustion engines and more particularly to two-cycle engines, theprimary object of my invention being the provision of an engine in whichthe cylinders are cast en bloc, one constituting a precolnpressioncylinder for the explosive mixture and the second the final compressionand firing cylinder, as many pairs of these cylinders being employed asdesired.

In this connection, a still further objeetof my invention consists inthe provision of a novel arrangement of the cylinders, their waterjackets and the transfer ducts between the precompression and firingcylinders, whereby the volume of the coolin system is increased withoutundue increase in size and weight of the motor, the explosive mixture ispreheated by the water jacketing during its first compression, its heatis maintained or increased during its transfer from the precompressionto the firing cylinder and cylinders are kept from overheating.

A still further object of my invention is t so arrange the fuel supplypipes, cyliners and transfer ducts that no valves will be exposed to theexploding or burning gases of the firing cylinders which does away withburnt out or carbonized valves and valve seats, thereby greatlydecreasin the necessity of re airs and adjustment and prolonging thelife of the motor.

A furtherolziject of my invention is to so construct the ring cylindersand the fuel supply ducts leading thereto that all chance of leakagefrom the firing cylinders is prevented.

Another object which I have in view is to increase the durability ofengines of the above described type and to simplify their constructionand reduce the necessary parts and decrease the care, skill andattention required to operate and'maintain it.

With these and other objects in view my invention will be more fullydescribed, illus trated in the accompan ing drawings, and thenspecifically pointe out in the claims Specification of Latte" Patent.

Application flied November 21, 101i. Ierlello.

and State 'lookin Patented May 21, 19! R.

which are attached to and form a part of this a plication.

In t e drawings:

Figure 1 is an elevation of an engine constructed in accordance with myinvention, at the fuel supply side and showing the va ve actuatingmechanism;

Fig. 2 is a central longitudinal vertical sectional view of the engine,showing the relative positions of the pistons;

Fig. 3 1s a fragmentary perspective view, showln one means oftransmitting power from t a crank shaft to the magneto shaft and valveoperating cam shaft of the enne- Fi 5: is a plan view of the en 'ne,showing tie fuel supply system to t e precompression' cylinders and fromsuch cylinders to the firingcylinders, parts of the engine not relatingto this being omitted for clearness;

Fig. 5 is a fragmentary vertical sectional view, showing one of thevalves controlling the supply of fuel to the precompression cylinders;

Fig. 6 is a corresponding view, showing one of the valves controllingthe passage of fuel from the recompresslon cylinders to the firing cyiiners.

orrespondiiig and like parts are referred to in the followingdescription and indieated in all the views of the drawings by the samereference characters.

For the sake of convenience, I have illustrated my invention as embodiedin an enand the upper portions and heads of the cylinders of each pairare surrounded by a common water jacket 11, as best shown in Fig. 2.These cylinders are mounted in the usual manner upon the upper section12 of a crank case 13, being secured thereon by bolts 14. The uppersection 12 and lower section 15 of the crank case have mating flanges 16through which are passe bolts 17 receiving nuts 18 and these crank casesections are formed to provide aliyled bearin e 19 for'a crank shaft 20having ra ity of crank arms or pins 20', one cylinder.

Each cylinder block includes a precomor each pression cylinder 21 andfiring cylinder 22, the firing cylinders being disposed adjacent eachother, while the precompression cylindcrs are located at the front andrear of the en ine. Pistons 23 operate in the cylinders an are providedwith the usual piston rings 24 to prevent leakage from the cylindersinto the crank casing. The pistons of the firing cylinders are alsorovided at their per ends with upwar y and inwardly irected batlles 25to direct incomin gases toward the upper ends of the cylin ers, as willbe later apparent. Piston rods 26 operatively connect the pistons withthe crank ins 20 of the crank shaft 20. At this point it should be notedthat the crank ins to which the pistons of the firing cylin are areconnected are set at 180 degrees to each other so that the pistons willmove in o posite directions to permit firing in one cy inder duringfinal compression in the other. It should also be noted that the crankpins to which the pistons of the precompression cylinders are connectedare dis used at 180 degrees to the crank pins to w ich the pistons ofthe corresponding firing cylinders are connected so that, upon the powerstroke of each firing piston, the corresponding precompression pistonwill be on its compression stroke.

The crank shaft, as is usual, pro'ects at its ends beyond the crankcasing an at one end carries a fly wheel or pulley 27. Its opposite endpro ects through a gear housin 28 and within such housing carries a pair0 sprocket wheels 29 and 30 which are fixed to the shaft by set bolts 31or other suitable means. Alined bearings 31', formed upon the upperportion of the crank case, journal a magneto shaft 32, one end of whichprojects into an extension of the hdusing 28 and carries a sprocketwheel 33. In like manner, a plurality of alined bearings 34, at the freeside of the crank case, journal a cam shaft 35, one end of whichprojects into the housing 28 and carries a sprocket wheel 36. A

sprocket chain 37 is trained about the sprockets 80 and 33, while asprocket chain 38 is trained about the sprockets 29 and 86 to providemeans for transmitting power from the crank shaft to the ma etc and camshafts. These sprockets are 0 suchsize as to drive the shafts 32 and 35at the same speed as the crank shaft.

Ducts 40, cast with the cylinder blocks, rovide inlet passages throughthe water ackets between the upper portions of the precompression cyliners and inlet valve chambers or casin' 41, also cast with the blocks,and rojecting from the sides of the c linders. ach valve chamber orcasing inc miss a cylindrical portion 42 disposed verticall above thecam shaft 35 and an outward minatmg in an attaching flange 44 whichdesired type.

y and laterally directed portion 43 ter=- will mate with the attachingflange 45 of a branch 46 of the in take manifold 47 which in turnconnects with a carburetor 48 of any As shown, the flanged ends of thesecasings are directed,toward each other and downwardly in order that a Y-sha ed manifold may be readily connected to 81cm. A valve seat 49 isformed in the vertical portion of each of the valve casings at a levelbelow scat an inlet valve 50 having a valve stem 52 projecting through astuffing box 53 threaded into the lower end of the cylindrical portionof the valve casing. The upper en of the cylindrical portion of thevalve casing is open and internally threaded to receive a cap 54 which,with a gasket or packing ring 55, tightly closes the valve casing. Castwith each cylinder block is also a duct 56 providing a passage from theupper portion of the precompression cylinder to the chamber or casing 57of the transfer valve, this casing also being cast integrally with theblock and projecting beyond the cylinder. Cast with each block is a duct58 which is formed wholly within the water jacket of the block and whichprovides a passage between the transfer valve casing. and that portionof the firing cylinder im-. mediately above the piston when the latteris at the lower portion of its stroke.

the duct or passage 40 to The ducts 58 provide transfer passages forthe,

ex losive mixture from the precompression cy inders to the firingcylinders and such passage of gas is controlled by a transfer valve 59cooperating with a seat 60 to either permit or shut olf communicationbetween -the duct 56 and duct 58. Thestem 61 of the valve 59 is passedthrough a stufiing box 62 threaded in the lower wall of the casing 57and the upper wall of the casing is formed with an opening to permit orimal insertion of the valve which is closed y a cap 63 cooperating with agasket or was er 64. These valve seats (SO-are disposed vet-- ticallyabove the cam shaft 35 and it should be noted at this point that boththe inlet valves and transfer valves open upwardly.

.The cam shaft 35 is rovided or formed with a plurality of crank'pins'65, one below each of the valve stems 52 and (Hand all preferablyhaving an equal th'row. A link 66 pivotally connects each crank pin witha push rod 67 which is reciprocally mount-' ed in a bracket 6,8 carriedby the-,crank casing and which, at its upper end, is provided with areduced threaded exteiflifih 69. Threaded into the extension is anadjusting screw 70 which may be secured in any de neld against movementby a cotter pin and a helical spring 76 surrounds each valve stemengaging between its Washer and the free end of the shell 72.

By this means, I provide a mechanism for positively closing, as well aspositively opening, the various valves as t e tendency of the spring 76is at all times, to holdthe valves closed and the valvesdwill open onlywhen the free ends of their'valve stems are engaged and lifted by theadjustable screws 70 of the push rods. The length of the push rods andconnectin links is such that the adjusting screws will engage theirrespective valve stems on y during the time ,of greatest upward throw ofthe corresponding crank )ins of the shaft and, as a result, the valveswill be opened for only a relatively short time, being held strongly totheir seats at other times b the springs.

Conductor cables 77 lea from the magneto to spark plugs 78 threadedthrough the heads of the firing cylinders 22 to supply a spark producingcurrent at the proper times. A water sup ly pipe 79, leading from aradiator or other source of supply, communicates with the water jacketsof the cylinder blocks and a return ipe 80 has branches 81 communicatinwit the upper portions of such jackets. ucts 82, cast integrally withthe lower portions of the firing cylinders 22, establish communicationbetween these cylinders and the branches of an exhaust pipe 83, theseducts opening into the cylinders atpoints slightly above the upper endsof the pistons when the latter are at the bottom of their stroke.

In considering the operation of my improved engine, it should be notedthat each block in efi'ect constitutes an engine unit, as many blocks,of two cylinders each, being employed as desired and all blocks actingthe same. Of course, however, the firing cylinders should be so arrangedas to insure alternate explosions in a twoblock engine in order tobalance the power exerted upon the crank shaft. Considering, therefore,a. pair of cylinders 21 and 22, and bearing in mind that the crank pinof the inlet valve is set to open the inlet valve as the piston of thecompression cylinder 21 approaches the end of its suction stroke and thecrank pin of the transfer valve is so set as to open the transfer valvejust prior mthe completion of the compression stroke, the operation maybe readily understood. During the down stroke of the piston of acompression cylinder, an explosive mixture is drawn into this cylinderand is compressed therein upon the upstroke of the piston, the inletcourse, being closed during its compression stroke. As this compressionstroke nears its end, the transfer valve opens and permits thecompressed gases to pass from the compression cylinder into the firingcylinder 22' ,gases admitted to the firing cylinder, as

valve, of

at the time when the piston in the firing cylinder has completed itsfiring stroke and the burnt gases are escaping throu h the outlet portof the cylinder. The bail e upon the piston, of course, directs theexplosive mixture toward the upper end of the firing cylinder and sokeeps it out of contact with theputcoming burnt gases. Upon the nextsuction stroke of the compression piston, the

above explained, are com ressed therein so .that when the iston in t efiring cylinder reaches or near y reaches its uppermost position, thesegases are ready for firing. The time of firing is, of course, determinedby a suitable timer in connection with the magneto and the charge willordinarily be ignited shortly before the piston in the firing cylinderreaches its highest point, the amount of lead so provided beingdependent upon the extent to which the spark control is advanced orretarded.

As the pistons in the firing cylinders lap, the inlet orts or passagesof such cylinders, during a most the'entlre time of firing, it will beclear that no valves are exposed to the burning gases and all burningout or carbonizing of valves and valve seats is, therefore, avoided.Alsr ll. possibility of any leaka from the Ling cylinders, except past te piston rings or about the spark plugs, is prevented. The compressionof the exp osive gases in the compression cylinders 21 prior to theircompression in the firing 0y inders,'serves to more thoroughly mix t egases and also to preheat them. Furthermore, inasmuch as the transferpassages between the compression cylinders and firing cylinders liealmost wholly within the water chamber or jacket of the engine, it willbe clear that any heat attained by this precompression is not lostduring transfer of the gases. Furthermore, by includin each compressioncylinder in the water jac ret of its corresponding'firing cylinder, thevolume of the cooling system, as a whole, may be increased withoutunduly increasing the size or weight of the motor and any overheating ofthe compression cylinders, due to too closely fitting pistons, will beavoided.

The pistons of the firing cylinders being connected to the intermediateportion of the be unders ood that I reserve the ri ht to make anystructural chan s and alterations in arrangement of arts w lch may befound advisable, within e scope of the appended claim, without in anyyvay departing from the spirit of my invention.

Hnvin thus described the invention, what is claimefi as new is:

In an internal combustion engine, a precom ression cylinder and firingcylinder cast an Zoe, a common water jacketing comletel inclosing thecylinder heads an inlet uct ldillg through the water jacixeting of theprecompression cylinder adjacent its head, an exhaust duct leading throuh the water jacketing from the firing eylin er in spaced relation to itshead, a valve chamber formed exteriorly of the water jncketing, a porteweb dividin the valve chamber, a duct ding from t e upper portion of theprecompression cylinder through the water acketing to the chamber at oneside of the web, a duct leadin from the chamber at the oppiosite side ofjac eting to the firing c substantially diametrica y opposite theexhaust duct ending therefrom, an inlet conduit communicating with thefirst duct of the precompression chamber, a valve, in the conduit havinga, stem pro'ecting through the wall of the conduit, a, valve in thechamber having a stem projecting through the wall of the chamber,pistons in the cylinders, a crank shaft having operative connection withthe pistons, and means driven from the crank shaft controlling theopening and closin of the valves through engagement with eir stems.

linder at a point e web through the water In teatimoil ylwhereof I aflixmly'si ature.

S RLEY O. KIR Lei-l

